ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

IMPACT FACTOR 2018: 0.741

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 16(1) (1996) 17-26
DOI: 10.7151/dmgt.1020


Martin Knor

Slovak Technical University, Faculty of Civil Engineering
Department of Mathematics, Radlinského 11, 813 68 Bratislava, Slovakia

L'udovít Niepel

Comenius University, Faculty of Mathematics and Physics
Mlynská dolina, 842 15 Bratislava, Slovakia


We show that the out-radius and the radius grow linearly, or ``almost" linearly, in iterated line digraphs. Further, iterated line digraphs with a prescribed out-center, or a center, are constructed. It is shown that not every line digraph is admissible as an out-center of line digraph.

Keywords: center, digraph, line digraph, radius.

1991 Mathematics Subject Classification: 05C20, 05C12.


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[6] M. Knor, L'. Niepel and L'. Soltés, Distances in Iterated Line Graphs, Ars Combin. (to appear).